It is a common practice in the cattle industry to dehorn beef calves at or before about 3 weeks prior to weaning and preferably before 8 weeks of age. Dehorning is considered an important safeguard that prevents the damage caused by horned cattle and the resultant carcass damage and losses. Dehorning at a young age minimizes the risks to the calf, the producer, and the purchaser. These risks include death in older calves, decreased live weight gains in the few weeks following dehorning of older calves, and the resultant loss in productivity.
Moreover, bruising caused by horned feedlot cattle has been reported to cost the world wide beef industry millions of dollars in losses from trimming damaged carcasses. Hornless cattle cause less injury and bruising to herd mates, and a saving on bunk space is possible with dehorned cattle. Moreover, the risk of injury to the operator is increased when working with horned cattle in confined areas, while the risks of death, illness and setback all tend to increase for calves dehorned at an older age.
The cow/calf producer's decision to dehorn and the timing (age) will be influenced by a variety of factors, including his facility, available labor force, expertise with the techniques, awareness of the impact of the procedure on calf health and productivity, and market for the calves. Normal management procedures provide a variety of convenient time and options for dehorning. At one day of age, for instance, the operator will typically apply an identification eartag and inject the calf with vitamin E-selenium, thereby requiring that the calf be restrained, and providing an opportunity to dehorn at the same time. Some producers prefer to batch the calves up weekly during calving season and dehorn many at one time.
Dehorning at an early age (less than about 8 weeks) reduces the risk of serious infection because the horn bud is removed without having to open the sinus (cavity) into the skull, as would occur when dehorning older calves. It is also preferable to avoid the summer and autumn periods when dehorning calves, since the risk of infection and fly strike is too great.
A variety of methods exist for removing horns, each with its own attributes and disadvantages. These include:
1. Polled Bull
The best method of dehorning is the use of a naturally polled bull in the breeding 109 program. The use of a naturally polled bull from naturally polled ancestors over hored breeding cows should result in the birth of polled calves. Continuous use of polled bulls over these female offspring should ensure that all calves continue to be polled. This method has obvious advantages where polled breeds are available with production characteristics similar to those in horned cattle.
2. Chemicals
Newborn calves (less than about 5-6 weeks of age) may be successfully dehorned by using caustic potash or caustic soda, which can be purchased in solid stick or paste form. The chemical destroys the horn-producing cells around the horn bud. In a common procedure the horn bud is exposed by pushing the hair back, and the caustic material is applied to the horn button. The hair is allowed to cover over the horn bud. Some operators prefer to clip the hair prior to applying caustic, which is said to help keep the caustic in place, reduce the risk of irritation to the cows udder and flanks, and reduce irritation to other facial skin of the calf.
This approach, though commonly used, involves several drawbacks however, including the need to avoid contact of the caustic material with the eyes of the calf or body of the user. It is also necessary to use gloves when applying the material, and to avoid application in rainy weather. Caustic pastes are inexpensive however, easy to use, and work well with minimal risk of scurs (residual horn growth). Care should be taken to ensure that the paste is applied only to the horn button and that the calf does not rub the horn against it's body. Otherwise, the paste can be rubbed off by the animal and/or it may run down the body, causing hair loss and irritation. As quantities of paste are lost in this manner, the effectiveness of the procedure can be greatly diminished, occasionally resulting in the formation of a deformed horn, which can be particularly difficult to remove.
3. Hot Iron Method
Application of a specially designed hot iron to the horn bud of the young calf will destroy the horn-producing tissue at the base of the horn. The system is bloodless and can be used at any time of the year on young calves up to 12 weeks of age. Depending on the age of the calf, anesthesia will be recommended. This method requires that the calf be adequately restrained, however, and excessive heat and application times will cause brain damage.
4. Dehorning Spoon or Tube
A number of devices provide a quick and efficient technique for removing horn buds in calves less than 8 weeks of age. They involve the use of a tube (4 sizes available) adapted to fit over the horn bud, and cover about 1/8 inch of skin around the horn base. The cutting edge of the tube is placed straight down over the horn, and the tube is pushed and twisted until the skin has been cut through. The cutting edge of the tube can be used to cut under the horn button area and remove it, after which some bleeding may occur and an antiseptic should be applied.
5. Barnes-Type Dehorners
This is a fast, simple dehorner to use on calves with horns 0.5 to 4 inches long. The handles of the apparatus are closed in a manner sufficient to fit knives over the horn. The instrument is positioned to remove a ring of skin with the horn, such that when the handles can be spread the handles apart quickly, closing the knives and removing the horn.
While dehorning has been an accepted part of cattle management for generations, greater awareness of animal welfare in recent years means that past methods can no longer be accepted without question. It must be appreciated that whatever temporary discomfort might be caused by dehorning is generally outweighed by the long-term benefits of having the whole herd flee from damage caused by horns.
In view of the cost, timing, and efficacy, however, as well as animal welfare and operator health and safety concerns, the cattle industry is ever in need newer and more effective methods and apparatuses for effectively dehorning cattle.